1. Field of Invention
The present invention relates to a method for controlling an internal combustion engine, in particular a supercharged engine.
2. Description of Related Art
As known, some internal combustion engines are provided with a turbocharger supercharging system, which can increase the power developed by the engine by exploiting exhaust gas enthalpy for compressing the air aspirated by the engine, and thus increasing volumetric intake efficiency.
A turbocharger supercharging system comprises a turbocharger provided with a turbine, which is arranged along an exhaust pipe to turn at a high speed under the bias of the exhaust gases expelled by the engine, and with a compressor, which is turned by the turbine and is arranged along the air feeding pipe to compress the air aspirated by the engine.
A rather evident turbo lag usually occurs when a considerable, sudden, rapid increase of torque or power is requested in low torque or power conditions (low rpm and slow speed, i.e. when the driver floors the accelerator pedal, e.g. for overtaking). Turbo lag is the tendency of engines with turbocharger of failing to respond with power to the fast pressing of the accelerator pedal, and is particularly annoying in the case of sports car applications, in which the turbocharger supercharging system allows to achieve high performance.
Turbo lag is mainly caused by the inertia moment of the rotor, and occurs in case of sudden, rapid request for more torque or power and because the pressure must increase in the overall volume of the circuit downstream of the compressor.
Various solutions have been suggested over the years to attempt to reduce turbo lag and to further improve the performance of engines provided with turbocharger. For instance, a variable geometry turbocharger or a turbocharger comprising a plurality of turbines in serial or parallel configuration etc. may be used. All the solutions known until now are in all cases particularly disadvantageous in terms of costs and overall dimensions.
It is the object of the present invention to provide a method for controlling an internal combustion engine, in particular supercharged by means of a turbocharger, which control method is easy and cost-effective to implement.